Suppose that $S=\set{ \colvector{-1 \\ 2 \\ 1},\, \colvector{ 3 \\ 1 \\ 2},\, \colvector{ 1 \\ 5 \\ 4},\, \colvector{-6 \\ 5 \\ 1} }$. Let $W=\spn{S}$ and let $\vect{y}=\colvector{-5\\3\\0}$. Is $\vect{y}\in W$? If so, provide an explicit linear combination that demonstrates this.